Dynamoelectric generators



Feb. 19, 1957 E. J. LINDBERG 2,782,323

DYNAMO ELECTRIC GENERTORS Filed April 18, 1952 4 sheets-sheet 1 ATTORNEY Feb. 19, 1957 Filed April 18, 1952 E. J. LINDBERG 2,782,328

nYNAMo ELECTRIC GENERAToRs 4 Sheets-Sheet 2 1N V EN TOR.

Feb. 19, 1957 E. J. LINDBERG 2,782,328

DYNAMO ELECTRIC GENERATORS Filed April 18, 1952 4 Sheets-Sheet 3 IN VEN TOR.

0 laf/4190 d, l /NOBG ATTORNEY Feb. 19, 1957 E. J. LINDBERG 2,782,323

DYNAMo ELECTRIC GENERAToRs Filed April 18, 1952 4 sheets-sheet 4 IN1/Ewan. y fowAo u. waas-@ .ATTORNEY United State Patent 2,782,328 DYNAMOELECTRIC GENERATGRS Edward J. Lindberg, Yonkers, Y. Application April 18, 1952, Serial No. 283,@42 21 Claims. (Cl. S10-112) In present day dynamoelectric machines, the electromagnetic induction process is broken down into two fundamental actions performed by the field from a magnetized pole held in a movable relative suspension with an inductive helix carrying a closed external circuit. First, the eld is driven into the core of the helix from some position outside the helix and, second, it is forcefully removed therefrom to the outside. The turns of the helix are usually imbedded in an iron armature for stronger magnetic penetration. This process is then usually compounded by substituting for the outside of the helix, the cores of adjacent helices in a chained annular arrangement around the traversed surface of the armature. However, the process then consists of forcefully impressing the field onto a core that is opposing it, simultaneously pulling the same field out ofra core that is attracting it. Such opposing and attracting fields.v are set up in the now adjacent cores by the current circulating in, and being induced in their surrounding helices by the movement of the applied field.

The basis of my invention herein described, provides for a different mode of performing the two fundamental actions for electromagnetic induction, then is now in use as described above, obtaining thereby a considerable saving in power.

Referring to the drawings, Figure 1 is a diagram representing a portionof the inductive units in a present day generator. Figure 2 is a diagram illustrating a departure from the arrangement of inductive units in Figure 1. Figures 3 and 7 are respectively, elevation and plan views of what l now consider a preferred form of a generator which embodies my invention. Figs. 4, 5 and 6 are graphical representations of the machine of Fig. 3, showing the parts in their different relative positions, progressively. Fig. 8 is a graph ofthe induced current pro: duced by the generator of Fig. 3. Fig. 9 is a diagram il lustrating a mode of connecting the inductive helices o f Fig. 3. Figs. 10, l1 and 12 are modifications of the machine in Fig. 3.

InvFig. 1, the four helices 49 are connected to an ex.- ternal circuit and contain iron cores. They representa part of the armature of a present day generator and are considered here moving as a body in the direction shown by the arrow, between the grouped and stationary ield poles NS. The lines joining each core with a pair of poles, represent the magnetic lines of force between the polesengaged with the cores of the helices. In Fig. 2, one'helix 49a and two auxiliary iron blocks 50, form an armature which moves as a body in the direction of the arrow through the pole gap of two Wholly separated magnetic field units which extend vertically. The resistance 4% bridged across the terminals of helix 49a represents an externally closed circuit.

When, as in present day generators, the attracting and opposing poles of the induced fields produced by the current induced and circulating in their surrounding helices occupy adjacent positionscnv the armature so that they may act jointly toward each pole of the applied field, a loss of driving effort is sustained in overcoming a magnetic eld pattern in the armature which poses a non-productive motor i'ield steadily in reverse.

rTheapplied field in Fig. 1, instead of pulling itself from the attracting core when sufficient strain is produced in it to overcome the magnetic strength of the attraction, finds it has no path to jump to as it has in Fig. 2, except into the adjacent core which contains an opposing field. Consequently, additional stress is required which develops a lag of the field. In Fig. 2 the applied field in moving onto the core of helix 49a, from the iron block Sti, eventhough the core will contain an opposing field, encounters no such lag. So, taking unit for unit of Figs. l and 2 there is less lag in the applied field and consequently a saving in power.

Not only do I achieve the gain of power adorded by the practical application of Fig. 2 in my generator, but a novel mode of overlaying the opposing field into the core of, the helix, results in further gains. Also, gains are developed by my invention in the inductive coupling of two abutted helices, to lower the inductive reactance of the helices while affording less drag to a departing ield.

In l-ig. 3 a machine is shown in elevation with the magnetic,l coupling between four pole rotors 31a, 3117, 31C and 31d, an inductive armature 20 containing a helix 4nd divided into four inductive helices 46a, flb, 40e and 40d and the accessory armature 3i). The helices of two inductanceV unitsare shown inter-connected and provided with two terminals 55a and 561;, across which a load is presumably connected. Figs. 4, 5 and 6 each show advanced positions or the same coupling and the paths of the applied fields 51, 52, 53, 54 and 55, through one h alf of a revolution of the rotors. Fig. 7 shows the same inductive units and their supporting members and driving unitsin horizontal section, and Fig. 8 is a graph of the current induced` in the helices during one revolution of the pole rotors. Fig. 3 also shows the division of the machine intotwo sections A and B.

The double poled rotors 31, are each mounted on a shaft 34. Around the neck of each pole is wound a magnetizing helix 32, shown bulked in Fig. 7. These helicesare connected to a source of direct current through collector rings 35, mounted on an insulating hub on each shaft. Each shaft is supported in two bearings 38, supported by end plates 36a and 36h, and attached to a spur gearing 33 in the gear housing which is at one end of the machine. These gears are intermeshed to transmit the driving power supplied through pulley 39, to each of the shafts so that each adjacent shaft rotates in the opposite direction evenly, at the same speed, as shown by the arrows on the rotors. The laminated ringed armature Ztl is carefully constructed from insulated thin sheets of armature iron or steel stampings which are held together by insulated rivets. The insulation is required to curb the formation of large eddy-currents in the core. inwardly projecting teeth on the armature 20 provide slots for imbedding the inside turns of the helices on the arced traversing areas. Four outwardly projecting ears 2S provide holes through which four supporting brass bolts 26 pass, each bolt is provided with two brass spacing sleeves 27a and 27h which hold the armature separated from the end plates 35a and 36h. Each bolt-is passed through a corresponding hole in the end plates and tightened up with a nut. The brass rods and spacers can he insulated from the armature as a preventive measure. The turns of the helices are insulated from and wound around the armature in one continuous direction, forming two inductance units between the terminals 56a and 56h, each covering a section consisting of two traverse arc core sections joined through a mean ridge 21a assenze and 2lb and extending to two extreme ridges 23a and 23h. The end turns of adjacent helices upon the extreme ridges 23a and 23h are abuttcd to obtain the best possible magnetic coupling of their magnetic fields. The accessory armature 39 which is interposed with the inductive armature 20, is separated therefrom in the traverse orbits of the rotor poles by two extreme gaps 24a and 24b and two mean gaps 22a and 22b, and is provided to reunite the magnetic fields of the rotor poles as they are dispersed from the armature 20. This armature is also constructed from armature iron or steel laminas held together with insulated rivets, observing necessary precautions to prevent the formation therein of large eddycurrents. This accessory armature is provided with a hole through its center in which a steel rod 29 is securely fastened, extending therefrom outward on each side toward the end plates 36a and 36b to which it is rigidly affixed to position it central of armature 20, and of the four rotors. The end plates are constructed from brass or any other substantial non-magnetic material, although they may be constructed from iron if they are kept sulficiently distant from the armatures magnetic influence or if a shield of copper is used between the armature 20 and the end plates, capable of repelling the field. Two foot plates 37a and 37b are provided on the base of the machine to which the end plates 36a and 36h are fastened to hold them in alignment and to provide a means of fastening the machine as unit.

Currents are induced in the turns of each helix 40 by altering the density or direction of the magnetic ux within the armature core 20 upon which they are wound, primarily by the continuously changing magnetic relationships maintained therein by the rotation of a pair of rotor poles in each section A and B, synchronized and set as shown in Fig. 3.

The inductive action in either section A or B is similar since one complements the other as will be later explained. Taking therefor, section A in Fig. 3, where the rotors are magnetized and rotating as shown, 52 represents the path of the applied field through the armature 20, and 51 represents a part of the opposite end of the same field which is now engaged with the accessory armature 30. The induced current in the helices at this point is shown on Fig. 8, point 44. From this position the rotors advance forty-five degrees to the positions shown in Fig. 4. The induced current reaches point 45 on Fig. 8, flowing in the helices 40 as shown by the arrows in Fig. 4, due to the transfer of field 51 from armature 30 across the gap 22h and the turns of the inductive helix 40 on the mean ridge 2lb, into armature 20. There are two applied fields in the core of the armature at this point, 51 and 52, and both fields although opposite ends of the same field are in opposition. An induced field presents a further opposition to 51 while aiding 52 and in this manner currents are induced in all the turns of the helices because weakening 51, weakens 52, which is part of the same eld. It is possible to assume that fields 5.1 and 52 unite as shown by the lines 55 in Fig. 4, and since equal parts of 51 and 52 will be lost to the part of the helix on this ridge section 2lb, there will be no current induced in the helix by the union. From this position the rotors advance another forty-five degrees to the positions shown in Fig. 5. The induced current reaches point 46 on Fig. 8, flowing in the helices 40 as shown by the arrows in Fig. 5, due principally to the separation of the two poles S-N from the armature at the cxtreme ridges 23a and 23h. The movement of the other two poles of the same rotors across the turns of the helices and in their effort to establish their field 51 across the mean ridge section, contributes somewhat to the induced current in this period. The rotors are in a position where field 52. finds it convenient to close through the accessory armature 30 while still maintaining an attachment with the inductive armature through the exe treme ridges 23a and 23h where it meets probably all of 51 which is held extended thereto by the overbearing surge of an induced eld in the whole section, however, since the strength of the induced field is controlled by the resistance of the load the helices are connected to, it is possible to assume that more or less, field 51 penetrates the mean ridge section at this time. The induced current is now at its highest peak and a strong field in this section A, is confronted with an equally strong opposing field from section B at the extreme ridge sections. This action will be explained later. From this position the rotors advance another forty-five degrees to the positions shown in Fig. 6. The induced current reaches point 47 on Fig. 8, flowing in the helices 40 as shown by the arrows in Fig. 6, due to field 51 receding from the extreme ridges 23a and 23b and the grasp of the induced field, and accumulating across the mean ridge 2lb, wherein it opposes the induced field. While this activity is incapable of sustaining the peak voltage developed in the last stage, it has the effect of throttling its rapid descent thereby developing its power. Field 52 is now wholly on the accessory armature 30, and this has a strengthening effect on field 5l. From this position the rotors advance another forty-five 'degrees to the positions shown in Fig. 3, except that now the rotors are advanced one hundred and eighty degrees and their polarity is opposite to that shown for this reference. The induced current reaches point 48 on Fig. 8, flowing in the helices as shown by the arrows in Fig, 6, due to a continuation of the same process that began in the last stage whereby field 51 overcomes the opposition of the field of the induced current across the mean ridge section 2lb. When the rotors reach the positions of Fig. 3, field 51 is at its maximum strength in the section and any further advance of the poles only serves to lengthen its path and thereby decrease its strength. Since the direction of the induced current will always oppose a magnetic change, it therefor commences a reverse trend following any further movement of the poles, as evidenced by the Sharp bend toward zero at point 48 in Fig. 8.

The generator has now completed a half revolution and in the following half revolution, field 52 will be returned to the armature via the mean ridge 2lb and unite with field 51, until field 51 is dispersed at the extreme ridges 23a and 23h, precisely as in the previous half revolution, except that the flow of induced current will be in the opposite direction as shown in Fig. 8.

While the magnetic fibre of armature section A, Fig. 3, is thus being changed by the action of fields 51 and 52 in inducing a current in the helices 40e` and 40d, a corresponding and similar cycle is taking place in section B which adjoins section A at the extreme ridges 23a and 23b. The rotors in section B are continuously in step with the rotors in section A, so that the details of operation presented above in section A are being duplicated by the fields 53 and 54 in section B, inducing a similar current in the opposite direction. The helices comprising each section are abutted on the extreme ridges 23a and 23b to couple them inductively so that their induced fields will balance out or dissipate one another as much as possible as the applied field withdraws. This action is similar to that of a transformer and it will enhance the productivity of the helices by lowering their inductive reactance and will enable the applied field to make a cleaner break-away at egress by providing an alternate engagement or partial cancellation of the induced fields. This feature is a practical development of my invention whereby the lag of the applied field at this point is negligible at all loads.

The rotors of either section may bc removed without interfering with the inductive cycle, but the quantity of induced current will be approximately halved. lt is not necessary to use all the helices of Fig. 3 in the same Y circuit, or these helices may be subdivided in any manner, or overlayed with separate helices, but the total current flowing in one section, A or B, will govern the available current in the other by ampere turns. If one has only a light current flowingV in it totaling two hundred ampere turns, the other section will not supply a total of more than two hundred ampere turns. But if one section is short circuited, the other will produce almost as much current as the two sections produce in parallel. This feature may be found practical for regulation of the output, by using one helix or the helices comprising one section to supply the load while the helices on the opposite section are shunted by a variable resistance, as shown in Fig. 9.

It should be clear from the foregoing explanations and descriptions that the inductive unit in my generator is quite different from that used in present day generators, and to distinguish this difference more clearly I offer the following resume.

The two rotors 33.0 and 31d in section A of Fig. 3 are each rotated in opposite directions within a pair of divided orbito-magnetic rotor chambers formed by the traverse arcs in the facing arced surfaces of two stationary masses or armatures and 30, two gaps 24a andl 2 4b at the extreme ridges 23a and 23h of armature 20, which form the principal gaps used in dividing the masses, and another gap 22h at the mean ridge 2lb of the same armature. One of these masses 20 contains the inductive helices 40e and 40d which furnish the electrical output `of the unit and is termed therefor the inductive armature. The second mass is provided for the purpose of` assisting the rotation of the rotors and preserving the strength of their magnetic fields, by reuniting them as their poles separate from the inductive armature, and maintaining such union for a period of their rotation thereafter in which they are disengaged with the inductive armature. This mass is therefor termed an accessory armature 30. The two rotors 31C and 31d each provide one magnetic field, the opposite ends of which terminate thereon at its two poles N-S which, by their synchronized, equal and opposite rotation in such a pair of adjacent chambers, are provided with the means to inter-connect their respective fields at appropriate intervals through the armatures, thereby providing a turbulent alternating linx in the inductive armature which generates useful and powerful electric currents in its helices.

The foregoing has described a basic inductive unit for generating electric current which may be advantageously coupled inductively to similar or identical inductive units, or used singularly and which, insofar as its practicability has been herein established as such, is nevertheless subject to variations in its design and construction necessitated by the required size of its component parts or to increase their purported usefulness in the economical production of a desirable current. In this respect, attention is called to the fact that this basic inductive unit may be inductively coupled in numerous multiple combinations with similar or identical inductive units comprising one machine and one inductive armature, in the same manner but in different sequences than those represented herein. To distinguish therefore this new inductive unit comprising a pair of orbite-magnetic lield rotor chambers with its rotors and inductive windings, I shall hereinafter refer to it as an inductive generator couplet, or just inductive couplet.

The rotation of the rotors Sie and 31d in an inductive couplet, are as shown by the arrows in Fig. 3, from the mean ridge 27th to the extreme ridges 23a and 2311 of the inductive armature 2d, when forward rotation is used. The inductive couplet is also capable of operation in the reversed rotation which will cause the ingress and egress of the applied fields to occur respectively at the extreme ridges 23a and 23h and the mean ridge 21, by rotating the rotors in the same synchronized, equal and opposite sense, but each inl the direction opposite to that shown. When one inductive couplet is operated in reverse rotation the adjoining coupletv can operate in either the reversed or forward rotation. A diagram of two adjoined inductive couplets using mixed rotation is shown in Fig. 11.

The inductive generator couplet is a practical'generator in its own right without any adjoining section as reproduced in Figs. 4 or 6. Its performance however is not as satisfactory as it would be with an adjoined secondary section at its extreme ridges as in Fig. 10, although its eiciency is better than that of a comparable present day generator.

The inductive generator couplet does not present a new theory ofv electromagnetic induction, because it is well known that an electric current is induced in a conductor by inductively associating it with a changing magnetic field. The couplet rather employs a novel process for constantly changing the magnetic fibre of a core wound with conductors forming an inductance unit to derive therefrom powerful electrical currentswithout undue attendance ofthe primary poles upon the induced magnetic field-of those currents.

The principle of my invention which is represented herein by the inductive generator couplet, is capable of reproduction in other arrangements for associating magnetized field poles with formed armature units in a dynamoelectric machine. All of these will employ a process equivalent to that in which the inductive generator coupletV successively disposes its primary elds in the core of its armature. That process is provided for in the form of the basic armature core unit and in its establishment as an arc segment of two separate pole traversing orbits, whereupon it is relatively movable with at least one successive bipolar magnetic field extended between the orbits from oppositely magnetized poles. The armature core form lfollows one magnetic axis whose length is `the sum of two pole-traversing arc sections plus a ridge-joining section. The traversing-arc sections extend larc-wise away from the ridge-joining section. The remaining portions of these pole traversing orbits contain arc sections of a pole accessory armature and magnetic gaps between it and the inductive armature.

Conductors can 'be wound around all of the sections of the inductive armature in one inductive generator couplet, and together they will form one inductance unit.

This process then, -concerns the manner in which a basic inductance unit is successively approached by, extensively penetrated with and subsequently detached from a bipolar magnetic field, whereby such bipolar field undergoes a displacement in length wholly within the core of such 'basic inductance unit, by the traversing movement thereupon of its poles during such penetration period. This penetration period moreover, allows time for a magnetic form to develop in consequence of a previous Ibipolar field detachment and a following bipolar field in traverse, representing a magnetic oscillation to the conductors forming the inductance unit, rather Ithan just a cutting action.

The bipolar fields are iborne to and away from the inductive armature core unit by the relatively mova'ble poles and a pole accessory armature which affords mobility to the bipolar fields. This accessory armature may even employ a motor winding supplied with appropriate electrical current increments to enhance its mobile magnetic character for the poles, as described later.

The inductive generator couplet will operate without an accessory armature Si), by extending the pole horns on each rotor or extending the extreme ridges 23a and Z315, or extending both to assist the poles in closing the gaps, although l prefer to use the accessory armature, as it strengthens the useful magnetic field. The mean gap 22h is not a necessary portion of the -orbito-magnetic field rotor chamber and this gap can be rbridged by a supporting rib 2511 as shown in Fig. ll, as described later, -although I prefer to present my principle in a form having a gap in Ithis position. The inductive generator couplet will also function with just one magnetized pole per chamber instead of two although its construction will require such extra elements as magnetic inter-rotor shaft bridging masses or an additional couplet on the side, using double-poled rotors, the poles being adjoined Athrough an offset in the 'body of the rotor, furnishing one pole'for each-of two separate rotor chambers on each rotor, although I prefer to use two poles per chamber.

In Fig. ll is shown a more convenient method of supporting an accessory armature 130 from the inductive armature in an inductive couplet, by the supporting ribs 25a and 25b which replaces the gaps 22a and 22h in Fig. 3. In this type of construction the assembly of the whole unit is simplified because both armatures, including the rib, are assembled from one stamping thus elirninating the need for the supporting shaft 29 in Fig. 3. Since the rib lengthens the core of the inductive armature and introduces added reluctance thereby, it should be kept as -narrow as possible and if necessary, it can be used jointly with the shaft 29.

In inductive couplets using forward or mixed rotation, the accessory armature may be provided with a motor winding 41 as shown in Fig. l2, which will be used periodically on each half revolution Ito pose a magnetic eld in the mass that will assist in the transfer of the poles across the extreme gaps 24a and 24b. Since this winding will have a current induced in it proportionately as the iield penetrates it, and this current could develop to proportions which would defeat the purpose of the Winding, its current is controlled lby the rheostat 43 and the commutator 42, which is adjusted to cut it out when the current induced in the motor wind-ing balances the current being fed into it. It also cuts in the winding just before the poles start Ito leave the inductive armature, or between the positions shown in Figs. 3 and 4. However, this is merely one convenient adaptation of a motor eld winding. A more extensive winding can be provided on this unit which, when properly lsequenced with electrical current increments of proper proportions, will considerably raiselthe efficiency of the unit.

The production of induced currents in inductive generator couplets responds to the magnetic intensity of the field in the pole rotors and the speed at which they are driven, comparable in a sense with present day generators. Also dependent upon the speed. is the frequency of alternations, and since this unit only develops one cycle per revolution, the rotors will generally be designed with a small diameter, especially for such frequencies as sixty cycles per second. The inductive couplet is therefore more adaptable for frequencies of twenty or twenty-live cycles. Polyphase circuits will require a separate armature and an inductive couplet for each phase. A twopart commutator may be adapted to one of the shafts for converting all or part of the output to direct or pulsating current and the helices may be subdivided and the lparts so formed connec-ted in parallel for higher amperage, or they may be all connected in series for higher voltage, or parts of all or any helix or helices may be separated and then connected in series `or parallel, for use in separate circuits.

The use of construction alternatives in inductive couplets such as using permanent magnets for the rotors, instead of electro-magnets, a non-toothed armature in place of the toothed armature, laminated pole rotors wholly or partially replacing solid iron rotors, or con- 4structing the gears from any other substantial material, or replacing the "cars by other means of interconnecting the rotor shafts properly, or providing for other means of connecting the driving unit to the generator than the pulley shown, or constructing the machine using other than ball bearings as shown, or constructing the machine for vertical operation instead of horizontal, or providing a housing for the whole machine instead of the open construction shown, or the use of compound windings on the pole rotors, instead of, or in addition to, the single winding shown, are optional arrangements which maybe employed.

Thus my invention provides a dynamoelectric machine with a distinctively novel inductive process involving a magnetic tracking system for each of its inductance units. Since various embodiments of the invention other than those disclosed herein may be employed without departing from the spirit of Ithe invention, I do not intend to `be limited to the specic disclosures contained herein, 'but desire to *be afforded the protection offered by the full scope of my appended claims.

I claim as my invention:

1. A dynamoelectric machine comprising the combinat-ion of one pair of magnetized double-poled rotors having parallel adjacent axes, means to rotate said rotors synchronously in opposite directions to cause two opposite poles, one on each of said rotors, to be brought into alignment on each half revolution, a stationary inductive armature core, said core forming two pole 4traversing arc sections, said arc sections being disposed concentrically respectively of said axes land adjoined through a mean yridge joining -section from which they extend oppositely and arc-wise outwardly to two separated extreme ridge areas, conductors inductively wound on said `armature core, and a stationary accessory armature, said yaccessory armature being disposed in magnetically isolated relation with respect to said extreme ridge areas.

2. A dynamoelectric machine comprising the combination of one pair of magnetized double-poled rotors having parallel adjacent axes, means to rotate said rotors synchronously in opposite directions to cause two opposite poles, one on each of said rotors, to be brought into alignment on each half-revolution, a stationary inductive armature core, said core having two pole traversing arc sect-ions, said arc sections being disposed concentrically respectively of said axes and adjoined through a mean ridge joining section from which they extend oppositely and arc-wise to two separated extreme ridge areas, conductors inductively wound on said armature core, a secondary inductive core unit, means connecting said second inductive core unit to said yarmature core through said extreme ridge areas, conductors inductively wound on said secondary core unit, and -a stationary accessory armature disposed in magnetically isolated relation between said two extreme ridge areas.

3. A dynamoelectric generator comprising the combination of a plurality of pairs of magnetized doublepoled rotors, means disposing the rotors of each said pair with their axes in parallel relation, means to rotate each pair of rotors synchronously in opposite directions to cause two opposite poles, one `on each of said -rotors of each said pair, to be brought into alignment on each half-revolution, a stationary inductive armature core, said core having a plurality of pairs of pole traversing arc sections, said arc sections of each pair being each disposed lconcentrically respectively of separate ones of said Ifaxes, conductors inductively wound on said armature core, and a stationary accessory armature having arc sections disposed concentrically of respective ones of said axes and in magnetically isolated relation with respect to the corresponding arc sections of said core.

4. A dynamoelectric machine comprising two rotors each having at least two diametrically disposed magnetized poles, said rotors being disposed for rotation about two parallel axes to thereby dene two adjacent pole traversing orbits, a first armature arc section disposed concentrically and extending partially only about one of said parallel axes, a second armature arc section disposed concentrically and extending partially only about the second of `said parallel axes, one end of each of said armature sections being joined together with the other end thereof separated to provide a magnetic gap in the armature circuit with respeet to each -ot said orbits, the are surfaces of said sections adjacent ysaid pole traversing orbits having magnetic interaction with the poles of said rotors,

conductors wound inductively on said sections and means to rotate said rotors synchronously in opposite directions for simultaneous pole traversal of said two arc sections to induce electric current in said conductors.

5. A dynamoelectric machine according to claim 4 further including athird armaturesection disposed in said gap in spaced. relation to` each of said first and second sections, said third armature section having two arc surfaces disposed concentrically `of said axes, respectively, in circular `alignment with the arc surfaces of said two sections.

6. A dynamoelectric machine according lto claim 5 wherein said first and secon-d arc sections intersect to form a first mean ridge andthe arc surfaces of said third `armature section intersect to form a second mean ridge disposed opposite said first mean ridge.

7. A dynamoelectric machine according to claim 5 wherein said first and second ar-c sections are joined together to form a first mean ridge section and the 'arc portions of said third armature section are joined together to form a second mean ridge section and means interconnecting sai-d two mean ridge sections.

8. A dynamoelectric machine according to claim 5 wherein said third larmature section has a conductor wound thereabout, and means to apply current to magnetize said third Iarmature section at proper polarity lto urge the poles of said rotors -in the direction of rotation thereof.

9. A 4dynamoelectric machine comprising a plurality of rotors each having at least 'two -diametrically disposed magnetized poles, said rotors being disposed for lrotation about separate parallel axes to thereby define a corresponding number of adjacent pole traversing orbits, an armature core having a plurality of joined arc sections one each disposed concentrically and extending partially only about one of said axes, respectively, to provi-de an armature gap adjacent each of said orbits, the arc surfaces thereof having magnetic interactive relation with the poles of said rotors throughout the extent :of each of said arc sections, conduct-ors wound inductively `on said sections and means coupling said rotors in pairs for rotation synchronously in opposite directions.

l0. A dynamoelectric machine according to claim 9 further including a second armature disposed centrally of said first mentioned armature, said second armature having a plurality of arc surfaces disposed with the centers of curvature in coincidence with said axes, respectively.

l1. A dynamoelectric machine according to claim l() wherein there are a plurality of arc sections joined together in pairs to form a mean ridge section between each of the `arc sections of each pair and the arc surfaces of said second armature are joined together in pairs to form a mean ridge section between the said surfaces of each pair, the mean ridge sections of the two armatures being in opposed relation.

l2. A dynamoelectric machine comprising four magnetised rotors each having diametrically disposed magnetized poles, said rotors being disposed for rotation about four parallel axes to thereby define four adjacent pole traversing orbits, an armature core having `four joined arc sections one each disposed concentrically and extending partially only about one of said axes, respectively, to provide an armature gap adjacent each of said orbits, the arc surfaces thereof having magnetic interactive relation with the poles of said rotors throughout the extent of each of said arc sections, a second armature disposed centrally of said four axes and having a plurality of arc surfaces one each having the center of curvature thereof in coincidence with one of said axes, respectively, conductors wound inductively on said sections and means to drive said rotors in pairs for rotation synchronously in opposite directions.

13. A dynamoelectric machine comprising an armature having an even number of arc sections greater than two, said are sections each being disposed about a different parallel axis tov define `ay corresponding number of pole traversing orbits, said arc, sections being joined together in pairs and extending to form two separate extremities per pair, conductors wound inductively on said arc sections whereby current fiowing therethrough induces magnetic poles at said extremities, a rotor disposed for rotation about each of said axes, each rotor having magnetized poles for movement in the orbit defined by Ian adjacent arc section and means to rotate said rotors synchronously in opposite directions.

14. A dynamoelectric machine according to claim 13 further including a second armature disposed centrally of said first mentioned armature, said second armature having 4'a number of arc surfaces corresponding to the number of said sections, each of said arc surfaces being disposed concentrically with respect to one of said axes and in circular alignment with the arc surface `of the corresponding section of said first armature.

l5. A dynamoeiectric machine comprising an inductive armature having a given magnetic axis extending arc-wise in two directions from the mid section thereof to provide two separate pole traversing arc sections each being disposed concentrically with respect to a different one of two parallel axes, conductors wound on said armature to accentuate the magnetic axis thereof, a magnetised pole unit disposed in coactive relation with respect to each of said arc sections to provide two separate armature-pole combinations, the armature arc section and pole unit of each such combination being relatively movable and means to effect synchronously and in opposite directions the relative movement in said combinations to induce magnetic fields in said arc sections for armature traversal in opposite directions symmetrically with respect to said mid section.

16. A dynamoelectric machine according to claim l5 further inciuding an auxiliary armature having two karc sections disposed in circular alignment respectively with the two arc sections of said inductive armature and means to maintain said auxiliary armature and said inductive armature in mutual magnetic restraint.

17. A dynamoelectric machine comprising an inductive armature having two parts disposed in opposed relation, each part having a magnetic axis extending arcwise in two directions from the mid section of the part to provide two separate pole traversing arc sections, conductors wound on said armature parts to accentuate the magnetic axes thereof, a magnetised pole unit disposed in coactive relation with respect to each of said arc sections to provide four separate armature-pole combinations, the armature arc section and pole unit of each such combination being relatively movable and means to effect synchronously and in opposite directions the relative movement in each pair of combinations associated with the two armature parts to induce magnetic fields in the corresponding arc sections of each armature part for armature traversal in opposite directions symmetrically with respect to the mid section of each armature part.

18. A dynamoelectric machine `according to claim 17 further including an auxiliary armature having four arc sections disposed in circular alignment respectively with the four arc sections of said inductive armature and means to maintain said auxiliary armature and the two parts of said inductive armature in mutual magnetic restraint.

19. An electro-mechanical transducer comprising an armature core having first and second pole traversing armature sections, said sections being joined together at one end and separated along the lengths thereof and at the other extremities thereof, conductors disposed transversely of said first and second sections, a second armature core having third and fourth pole traversing armature sections joined together and interposed between the extremities of said first and second sections but in spaced relation thereto to provide a magnetic armature gap in each of the two armature paths thus formed by the firstthird, and second-fourth sections, respectively, a magnetic pole arrangement including a pair of poles of opposite polarity, said pole arrangement and said armature cores being relatively movable and the poles of said pair being arranged to traverse said armature paths in unison during such relative movement.

20. A dynamoelectric machine according to claim 1S further including conductors on said auxiliary amature.

21. A dynamoelectric machine according to claim 19 further including conductors on said second armature core.

References Cited in the le of this patent UNITED STATES PATENTS Trumpler Dec. 28, 1926 FOREIGN PATENTS Great Britain May 15, 1919 France Aug. 18, 1909 

